U.S. patent application number 16/677950 was filed with the patent office on 2020-03-05 for digital otoscope.
The applicant listed for this patent is Welch Allyn, Inc.. Invention is credited to Eric M. Andreassen, John T. Delaney, Corinn C. Fahrenkrug, David M. Fallat, Ervin Goldfain, Howard Haines, Cynthia A. Kuiper, John R. Strom.
Application Number | 20200069167 16/677950 |
Document ID | / |
Family ID | 40394174 |
Filed Date | 2020-03-05 |
United States Patent
Application |
20200069167 |
Kind Code |
A1 |
Andreassen; Eric M. ; et
al. |
March 5, 2020 |
DIGITAL OTOSCOPE
Abstract
An otoscope includes an instrument head, a tip element and an
optical system. The instrument head has a distal insertion portion
for insertion into an ear of a human or veterinary subject. The
distal insertion portion has a distal opening. The tip element is
releasably attached to the distal insertion portion. The tip
element has a distal opening. The optical system is contained
within the instrument head. The optical system includes a plurality
of optical components. The optical system further comprises a
viewing component for viewing of an image of a target of interest
aligned along an optical axis disposed within said distal opening.
The optical system is configured to provide a field of having a
diameter equaling at least 7 mm at a distance of at least 15 mm
from a distal opening of said attached tip element. The optical
system is further configured to simultaneously provide a distance
range of optimal focus having a range of at least 8 mm. The
distance range of optimal focus includes a location at a working
distance equal to about 30 mm.
Inventors: |
Andreassen; Eric M.;
(Syracuse, NY) ; Fallat; David M.; (Auburn,
NY) ; Goldfain; Ervin; (Syracuse, NY) ; Strom;
John R.; (Moravia, NY) ; Delaney; John T.;
(Auburn, NY) ; Haines; Howard; (Auburn, NY)
; Fahrenkrug; Corinn C.; (Liverpool, NY) ; Kuiper;
Cynthia A.; (Syracuse, NY) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Welch Allyn, Inc. |
Skaneateles Falls |
NY |
US |
|
|
Family ID: |
40394174 |
Appl. No.: |
16/677950 |
Filed: |
November 8, 2019 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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15332110 |
Oct 24, 2016 |
10470650 |
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16677950 |
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13899803 |
May 22, 2013 |
9474441 |
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15332110 |
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13237022 |
Sep 20, 2011 |
8469882 |
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13899803 |
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11845512 |
Aug 27, 2007 |
8066634 |
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13237022 |
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10897590 |
Jul 23, 2004 |
7399275 |
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11845512 |
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60543858 |
Feb 11, 2004 |
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60507473 |
Sep 30, 2003 |
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60490566 |
Jul 28, 2003 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61B 1/00096 20130101;
A61B 1/227 20130101 |
International
Class: |
A61B 1/227 20060101
A61B001/227; A61B 1/00 20060101 A61B001/00 |
Claims
1. A digital medical diagnostic instrument comprising: an
instrument head including a distal insertion portion at a distal
end and a proximal end; an optical system disposed within the
instrument head, the optical system including at least one distal
objective lens aligned along a viewing axis; a handle portion
containing at least one battery, the instrument head being attached
to the handle portion; a digital image forming device aligned along
the viewing axis and configured to receive an image of a medical
target from the optical system; and at least one control button for
enabling a first normal viewing mode and a second zoom
magnification mode.
2. The instrument of claim 1, further comprising a tip element
releasably attached to the distal insertion portion.
3. The instrument of claim 2, in which the instrument is an
otoscope configured to examine a body cavity including an ear canal
or a nasal cavity.
4. The instrument of claim 1, further comprising an accelerometer
for detecting an orientation of the instrument.
5. The instrument of claim 4, in which the accelerometer is coupled
to the digital image forming device, the digital image forming
device being configured to reverse an image of a medical target by
180 degrees when the accelerometer determines that the instrument
is being held in a reverse orientation by 180 degrees.
6. The instrument of claim 1, wherein the at least one control
button is configured to permit toggling between the first normal
viewing mode and the second zoom magnification mode.
7. The instrument of claim 1, in which the zoom magnification mode
magnifies a center portion of a default field of view of the
digital image forming device obtained in the first normal viewing
mode.
8. The instrument of claim 7, in which the center portion of the
default field of view is approximately one half of the diameter of
the field of view.
9. The instrument of claim 1, further comprising a microphone
configured to input audio information for storage and communication
with image information of the digital image forming device.
10. The instrument of claim 1, further comprising a display coupled
to the digital image forming device.
11. The instrument of claim 1, further comprising a focusing
mechanism for axially moving at least one lens of the optical
system.
12. The instrument of claim 1, in which the proximal end of the
instrument head includes an eyepiece.
13. The instrument of claim 1, in which the digital image forming
device is attached to the instrument head.
14. The instrument of claim 1, in which the digital image forming
device is disposed within the instrument head.
15. The instrument of claim 14, further comprising a focusing
mechanism for axially moving the digital image forming device
relative to the optical system.
16. The instrument of claim 1, including a communication channel
for transmitting images obtained by the digital forming device to a
remote location.
17. The instrument of claim 16, in which the communication channel
is wireless.
18. The instrument of claim 1, further comprising memory for
storing images obtained by the digital image forming device.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This patent application is a continuation application of,
and claims priority and benefit to, co-pending U.S. patent
application Ser. No. 15/332,110, filed Oct. 24, 2016, entitled
"Digital Otoscope", which is a continuation of U.S. patent
application Ser. No. 13/899,803 filed May 22, 2013, entitled
"Digital Otoscope" and now issued U.S. Pat. No. 9,474,441, which is
a divisional application of U.S. patent application Ser. No.
13/237,022 filed Sep. 20, 2011, entitled "Digital Otoscope" and now
issued U.S. Pat. No. 8,469,882, which is a divisional application
of U.S. patent application Ser. No. 11/845,512 filed Aug. 27, 2007,
entitled "Digital Otoscope" and now issued U.S. Pat. No. 8,066,634,
which is a continuation-in-part application of U.S. patent
application Ser. No. 10/897,590 filed Jul. 23, 2004, entitled
"Otoscope" and now issued U.S. Pat. No. 7,399,275, which claims
priority based upon the following provisional patent applications:
U.S. Ser. No. 60/490,566, filed Jul. 28, 2003; U.S. Ser. No.
60/507,473, filed Sep. 30, 2003; and U.S. Ser. No. 60/543,858,
filed Feb. 11, 2004. All of the aforementioned patent(s) and patent
application(s) are herein incorporated by reference in their
entirety.
FIELD OF THE INVENTION
[0002] This invention relates generally to an otoscope that
incorporates an image forming device, such as a digital camera, and
in particular to an otoscope further providing optical
characteristics that enhance medical inspection of both human and
veterinary subjects.
BACKGROUND OF THE INVENTION
[0003] An otoscope is used for inspection of an ear canal or a
nasal cavity. Typically, a prior art otoscope includes one or more
lenses providing a fixed magnification of light received, without
providing a separate mechanism for adjusting focus over any
significant range, if over any range at all. Whether a particular
target within the ear canal, such as the tympanic membrane (ear
drum), is at or near optimal focus with respect to the observing
eye of a medical practitioner, generally depends upon the location
of the otoscope with respect to the target.
SUMMARY OF THE INVENTION
[0004] In one aspect, the invention provides for a digital otoscope
for forming (imaging) live and still digital images of anatomical
details of a body of a human or veterinary subject, and having
associated optical characteristics that improve the quality of
visual information gathered for medical inspection of both human
and veterinary subjects.
[0005] The digital otoscope is configured to attach to a tip
element having dimensions that are small enough to fit into a small
body cavity, such as an ear canal, nasal cavity or throat cavity,
for example. An attached tip element can be selected from a
plurality of different tip elements that are each configured to
attach to the otoscope 1000. An attached tip element and the
otoscope 1000 enclose an assembly of optical components yielding
optical characteristics that provide a substantially wide field of
view and a substantially wide range of optimal focus from which to
form visual information within a small and confined ear, nasal or
throat cavity, for example.
[0006] In some embodiments, the tip element is configured to be
inserted at least 15 mm into a representative human ear canal, and
configured to provide optical characteristics that include a field
of view of at least 7 mm at a distance of less than 10 mm from a
distal end of the tip element, and a distance range of optimal
focus starting at less than 5 mm from a distal end of the tip
element and extending greater than 20 mm from a distal end of the
tip element.
[0007] The foregoing as well as other objects, aspects, features,
and advantages of the invention will become more apparent from the
following description and from the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The objects and features of the invention can be better
understood with reference to the claims and drawings described
below. The drawings are not necessarily to scale, the emphasis is
instead generally being placed upon illustrating the principles of
the invention. Within the drawings, like reference numbers are used
to indicate like parts throughout the various views. Differences
between like parts may cause those parts to be indicated by
different reference numbers. Unlike parts are indicated by
different reference numbers.
[0009] FIG. 1 illustrates a top perspective view of an embodiment
of a digital otoscope that incorporates a digital image forming
device and that is in communication with a computing device via a
communications channel.
[0010] FIG. 2 illustrates a side cross-sectional view of the
embodiment of the digital otoscope.
[0011] FIG. 3 illustrates an exploded view of internal components
of the embodiment of the digital otoscope.
[0012] FIG. 4 illustrates a side cross-sectional view of the lens
train of the digital otoscope.
[0013] FIG. 5 is a diagram representing the field of view and the
entrance pupil in relation to the most distal lens located within
the tip element of the digital otoscope.
[0014] FIG. 6A is a diagram representing a distance range of
optimal focus provided by the human configuration of the digital
otoscope.
[0015] FIG. 6B is a diagram representing a distance range of
optimal focus provided by the veterinary configuration of the
digital otoscope.
[0016] FIG. 7A is an illustration of a typical human ear canal.
[0017] FIG. 7B illustrates a representative human ear canal.
[0018] FIG. 8 illustrates placement of the tip element within the
representative human ear canal.
[0019] FIG. 9 illustrates an image of a tympanic membrane formed
from the digital otoscope 1000 at or near optimal focus.
DETAILED DESCRIPTION OF THE INVENTION
[0020] FIG. 1 illustrates a top perspective view of an embodiment
of a digital otoscope 1000 that incorporates a digital image
forming device (See FIGS. 2-3) and that is in communication with a
computing device 1090 via a first communications channel 1050. In
this embodiment, the image forming device is implemented as a
digital camera and the communications channel 1050 is implemented
as a wireline (cable connection) type of communications channel
1050 and the computing device 1090 is implemented as a personal
computer 1090.
[0021] In this embodiment, the digital camera is embedded into the
housing of the digital otoscope 1000 (See FIGS. 2-3). The digital
camera is configured to form image information that represents a
still or a live image. In this embodiment, the digital camera is
implemented as a Micron 1/3 Inch SOC Megapixel CMOS Digital Image
Sensor, also referred to herein as the image sensor or imager. In
other embodiments, other models of digital cameras from the same or
different suppliers, are employed to function as the image forming
device.
[0022] As shown, the otoscope 1000 includes an instrument head 18
including a surrounding housing 1020 and a distal insertion portion
29 that is insertable into an ear canal. An optical axis 27 is
defined as being nearly (proximately) centric to a field of view of
the imager. A focus position visual indicator 209 is located along
a surface 202, also referred to as a recessed surface 202, that is
recessed with respect to the surface of the housing 1020. The
recessed surface 202 is a gripable elastomeric cover 202 that is
configured so that a user of the otoscope 1000 can press against
and push it in a direction that is tangential to its surface 202,
to rotate it around the optical axis 27.
[0023] The imager forms live (moving) or still images using an
array of 1280.times.1024 pixels having an aspect ratio of (5:4).
While operating in a live mode, the imager streams (communicates
over time) live images while employing an interspersed
640.times.512 subset (one quarter)) of the array of pixels, herein
referred to as currently active pixels. The remaining interspersed
pixels are blanked and herein referred to as currently inactive
pixels. While operating in live mode, upon capturing a still image,
the imager instead employs all 1280.times.1024 pixels to represent
the formed still image, utilizing all pixels as currently active
pixels.
[0024] In this embodiment, live images are streamed (communicated)
in real time without any significant portion of the live image
being first stored within the otoscope 1000. In other embodiments,
at least a significant portion of a live image is stored within the
otoscope 1000 before and if any communication of the live image is
performed.
[0025] Typically, the formed image information represents a view of
tissue within a portion of a body cavity such as an ear canal or
nasal cavity. While being formed, the object of interest is located
within a field of view of the otoscope 1000 (See FIG. 5). The
diameter (linear extent) of the field of view is determined by
optical characteristics of the otoscope 1000. The field of view can
be altered via a zoom magnification mode. When the zoom
magnification mode is on, a center portion (subset) of the default
field of view is magnified and represented by the currently active
pixels. The default field of view is active when the zoom
magnification mode is off.
[0026] While operating with zoom magnification mode off, an entire
field of view is represented by the currently active pixels. While
operating with zoom magnification mode on, a central portion
(approximately one-half of the diameter) of the entire field of
view is represented by the currently active pixels.
[0027] A proximal end of the otoscope 1000 includes to two
elastomeric push buttons 1002a-1002b, also referred to as
elastomeric switches 1002a-1002b. Two buttons 1002a-1002b are
provided to accommodate both right and left handed users of the
otoscope 1000. A pressing of either push button (switch)
1002a-1002b causes the imager to form an image, or to toggle a zoom
magnification mode of the imager, or to rotate the image currently
being formed by 180 degrees.
[0028] When either elastomeric push button 1002a-1002b is pressed
and released within a span of time that is less than two seconds,
the imager forms an image. When either elastomeric button
1002a-1002b is pressed and released in a span of time that is
greater than 2 seconds, the imager toggles its zoom magnification
mode (off is the (default)). When both elestomeric buttons
1002a-1002b are pressed and released in a span of time that is
greater than 4 seconds, the imager rotates an image currently being
formed by 180 degrees.
[0029] While in use, the otoscope 1000 is designed to be held
(oriented) in an upright position (as shown), referred to as a
hammer position, or held in an upside down position (not shown),
referred to as a pencil position. In other embodiments, the
otoscope 1000 includes an accelerometer (not shown) which detects
the orientation of the otoscope 1000 in order to reverse the image
rotation by 180 degrees, when the otoscope orientation is reversed
by 180 degrees.
[0030] In this embodiment, the communications channel 1050 is
implemented as a universal serial bus (USB) version 2.0. A USB
cable connector 1004 is disposed at the rear end of the otoscope
1000. A USB cable 1050, constituting the first communications
channel 1050, is attached to a proximal (rear) end of the digital
otoscope 1000 via the USB cable connector 1004. The image
information formed by the image forming device, namely the imager,
is communicated via the communications channel 1050 from the imager
to the personal computer 1090, also referred to as a computer 1090.
In other embodiments, the image information is stored into memory
within the otoscope 1000 before being communicated via the
communications channel 1050.
[0031] In other embodiments, the otoscope 1000 is configured to
provide memory to store digital information, such as including
image information. The memory is implemented as volatile random
access memory (RAM) or non-volatile flash memory. In some
embodiments, the memory is configured to be separable and portable
from the otoscope 1000. In some embodiments, the portable memory is
implemented a portable universal serial bus (USB 2.0) compatible
memory, such as a portable memory that is configured to
interoperate with digital cameras, or as portable memory within a
thumb drive, provided by suppliers including the Scandisk
Corporation.
[0032] The computer 1090 is located a distance away from the
otoscope 1000. Typically, the distance away at which the computer
1090 is located is within the vicinity of the otoscope 1000, such
as within the same room or same office space that the otoscope 1000
is being used. In other embodiments, the computer is located
farther from the otoscope 1000.
[0033] The first communications channel 1050 enables the digital
otoscope 1000 to communicate the image information formed by the
imager to the computer 1090 for visual display, and/or for
processing, and/or for storage and/or for further communication to
another computing device (not shown) via a second communications
channel (not shown).
[0034] The computer 1090 can be implemented from one of a variety
of computing platforms. Preferably, each computing platform
executes operating system software 1090c including one or more
device drivers for interfacing with devices associated with the
computer 1090.
[0035] In this embodiment, the computer 1090 executes the Microsoft
Windows XP operating system software 1090c and the otoscope 1000 is
configured to interoperate with the Windows XP device drivers as a
Windows Operating System standard video device. Interoperation is
bi-directional so that at least command and configuration
information can be communicated from the computer 1090 to otoscope
1000 and image information can be communicated from the otoscope
1000 to the computer 1090.
[0036] This embodiment enables the otoscope 1000 to interoperate
with the Windows XP operating system software as a plug and play
device and further enables a user to utilize a variety of software,
including the Windows XP Explorer browser program and other
Microsoft Windows based video processing application software, to
display and process image information.
[0037] Optionally, other operating systems and other browser
programs and can be installed and executed by the computer 1090.
Preferably, the operating system is compatible with the USB 2.0
standard. For example, the Vista operating system supplied by
Microsoft, the Linux operating system, versions of which are
supplied from Red Hat and other suppliers, and the Apple Macintosh
operating system can be installed and executed on the computer
1090. Other browsers, for example, that are compatible with
particular operating systems, such as the Mozilla Firefox or the
Apple Safari browsers and can be installed and executed on the
computer 1090 where compatible.
[0038] The otoscope 1000 includes permanently stored digital logic,
also referred to as firmware (not shown), executed by a processor
(not shown) that is embedded within the otoscope 1000. The firmware
is configured to enable streaming video from the otoscope 1000 to
the computer 1090 and downloading of software from the computer
1090 to the otoscope 1000 via the communications channel 1050.
[0039] Software that is downloaded to the otoscope 1000 can alter
or add to the functionality of the otoscope 1000. For example,
downloaded software can recalibrate and/or re-program the operation
of the otoscope 1000. Software, referred to as (otoscope resident)
computer interface software, can function to interoperate with the
host computer and (host resident) computer interface software, to
enhance the interoperation between the otoscope 1000 and the host
computer 1090.
[0040] In some embodiments, a host device driver and/or other
software, referred to as (host resident) computer interface
software, is supplied for installation onto the computer 1090 and
interoperation with the digital otoscope 1000. The host device
driver and other software can be installed via the Internet or via
portable media such as for example, a compact disc or a USB port
compatible memory.
[0041] For embodiments involving the Microsoft Windows operating
system, the host device driver is configured to be compliant with
the Microsoft Windows Driver Model Connection Streaming
Architecture (WDM-CSA). In some embodiments, the other software is
supplied to provide functionality to perform still image
processing, device calibration, or to conform to other
manufacturing requirements etc. For example, in some embodiments,
the supplied software can function to trigger otoscope image
forming and capture from the host computer 1090.
[0042] Alternatively, the first communications channel 1050 can be
implemented as another type of wireline communications channel,
such as complying with the IEEE 1394 standard, a version of which
is known as Firewire. Or, the first communications channel 1050 can
be implemented as a wireless communications link, such as complying
with wireless communications standards including the IEEE 802.11 or
IEEE 802.15. A version of the IEEE 802.15 standard is known as the
Bluetooth wireless communication standard.
[0043] The topology of the first communications link can be a point
to point communications link, or as a local or wide area network
communications link. Like the first communication channel 1050, the
second communications channel can be implemented as a wireline or
wireless type of communications link and further as point to point,
or as a local or wide area network type of communications link.
[0044] In some embodiments, the computing device can be implemented
as a computing device that is smaller and more portable than a
personal computer, such as a personal digital assistant (PDA). Some
PDA's are configured to execute Windows XP and can interoperate
(transmit command and configuration information to and receive
image information from) the otoscope 1000, as a Windows plug and
play device.
[0045] In some embodiments, the computing device is configured to
execute non Microsoft operating systems. For example, computers
supplied by Apple Computer employ a NuBus architecture and also
provide plug and play functionality. In this embodiment, the
otoscope 1000 and its firmware are configured to interoperate with
plug and play functionality of operating systems supplied by Apple
Computer.
[0046] In some embodiments, image information can be transferred to
a smaller device, such as an Apple IPod computing device. For
example, in some use scenarios, image information is transferred
from the personal computer 1090 to an IPod device (not shown) via
the second communications channel.
[0047] FIG. 2 illustrates a side cross-sectional view of the
embodiment of the digital otoscope 1000 of FIG. 1. The structure of
the digital otoscope 1000 is mostly the same as the structure
described for the non-digital otoscope (associated with a figure
reference number 10) that is described within the parent patent
application Ser. No. 10/897,590, herein also referred to as the
'590 patent application, which is incorporated herein by
reference.
[0048] Like the non-digital otoscope (10) described within the '590
patent application, the structure of the digital otoscope 1000
includes an instrument head 18, a (conical) tip element 40 having a
distal end 44, a tip element retainer member 240, a distal
axisymmetrical insertion portion 29 having a distal opening 29a,
rotatable actuator knob 252, an inner former assembly 116,
cylindrical sleeve member 144, illumination assembly 124, lamp
retainer 140, and 128 miniature incandescent lamp, for example.
[0049] Further, the otoscope 1000 includes the same illumination
and pneumatic system design, the same tip element attachment and
removal mechanism and much of the same optical system design as
described within the '590 patent application. The otoscope 1000 has
much of the same focus mechanism as that of the '590 patent
application. For example, the housings, focus wheel, compression
spring and ball of the otoscope 1000 are the same as the
non-digital otoscope (10) and provide the same detent related
functionality and feel as provided by the non-digital otoscope
(10).
[0050] Unlike the non-digital otoscope (10) described within the
'590 patent application, the structure of the digital otoscope 1000
includes along its optical axis 27, components that are not
included among the components of the '590 patent application, in
order to interoperate with the image forming device 1020, which is
not included within the '590 non-digital otoscope. For example, the
digital otoscope 1000 includes a new lens doublet 1406 and 1408
(See FIG. 4) that is not included within the lens train of the '590
patent application.
[0051] Also, unlike the non-digital otoscope 1000 described within
the '590 patent, the digital otoscope 1000 excludes the components
of the '590 lens train, except for the lens doublet 96, 100. The
non-digital otoscope 1000 excludes a first relay lens (104), a
second relay lens (112), and lenses (190, 194) of the eyepiece
mechanism, for example. Further, the digital otoscope 1000 excludes
lens retainer member (176) and a ball 204, for example.
[0052] Within the non-digital otoscope (10), the focus adjustment
mechanism (focus wheel) moves one or more lenses in an axial
direction to adjust focus. Within the digital otoscope 1000, the
focus adjustment mechanism (focus wheel) instead moves the imager,
and not a lens, in an axial direction to adjust focus.
[0053] In some embodiments, the digital otoscope 1000 includes an
audio input device, such as a microphone (not shown), that is
configured to input audio information for storage and communication
in association with the image information of the image forming
device. The audio information can provide a timely explanation of
the image information as it is formed, in order to enhance digital
documentation of a medical inspection procedure.
[0054] In some embodiments, the otoscope 1000 includes a view
finder to enable the user of the otoscope 1000 to view an image
through the view finder of the otoscope at the moment of capturing
an image. The view finder can be implemented as one or more eye
piece lenses or as a liquid crystal display (LCD) attached to or
included within the otoscope 1000.
[0055] To accommodate the view finder, the optical axis 27 can be
folded, meaning that the optical axis 27 is split and a copy of the
image is redirected to the view finder. In some embodiments, a
single lens reflex (SLR) mirror or a beam splitter component is
employed to direct the image to the image forming device and the
view finder.
[0056] FIG. 3 illustrates an exploded view of a set of components
residing along the optical axis 27 of the digital otoscope 1000.
These components are located internal to the otoscope 1000 and are
designed to enable interoperation of the imager 1202 with other
components of the otoscope 1000.
[0057] As shown, the set of components includes an innerformer and
cone assembly including an optics tube assembly 1310, a housing
1312, a user focus adjustment 1314, a spring 1316, an imager holder
1318, an infrared (IR) filter 1320, a face seal (dust seal for the
imager) 1322, an imager 1202, an imager circuit board 1326, a USB
board 1328, an imager adjuster nut 1330, a connector board 1332, an
elastomeric switch 1334 and a bezel 1336.
[0058] When the otoscope 1000 is fully assembled, the user focus
adjustment 1314 rotates synchronously with the focus position
visual indicator 209. This mechanism enables the user of the
digital otoscope 1000 to perform focus adjustment and to achieve
optimal focus at a particular location that is selected by a user
of the otoscope 1000.
[0059] FIG. 4 illustrates a side cross-sectional view of the lens
train of the digital otoscope 1000. Like the non-digital otoscope
(10) described within the parent '590 patent application, the lens
train 1400 of the digital otoscope 1000 includes a lens doublet 96,
100 and a lens tube 1402, an o-ring 1412 and a retainer 1414 which
is the same as that of the non-digital otoscope (10) described
within the parent '590 patent application.
[0060] Unlike the non-digital otoscope (10) described within the
parent '590 patent application, the lens train 1400 includes a new
spacer 1404, a new lens doublet 1406 and 1408, a new aperture 1410,
and a new imager plane 1416. The imager plane 1416 and a plane of
optimal focus are located at the same location.
[0061] Unlike the non-digital otoscope (10) described within the
'590 patent application, the lens train 1400 does not include a
first relay lens (104) and a second relay lens (112) and lenses
190, 194 of the non-digital otoscope described within the '590
patent application. The lenses 190,194 move within the non-digital
otoscope in response to focus adjustment.
[0062] FIG. 5 illustrates a side cross-sectional view of the tip
element 40 along the optical axis 27 of the otoscope 1000. As shown
from this view, the distal lens 96 and a distal entrance pupil 1420
are located inside of the tip element 40. The most distal end 44 of
the tip element 40 includes an opening 44b surrounded by a wall.
The most distal end 44 with its opening 44b, functions as an
aperture that limits light rays entering the tip element 40. The
opening 44b is circular in shape (not shown from this perspective)
and is substantially perpendicular to the optical axis 27.
Furthermore, the opening 44b is oriented substantially parallel to
and accordingly, is also referred to as facing the field of view
1510.
[0063] The opening 44b has a diameter typically equal to about 4.24
mm, also referred to as an inner diameter of the most distal end of
the tip element 40. The wall of the tip that surrounds the most
distal end of the tip element has a width equal to about 0.38 mm.
Hence, the outer diameter of the most distal end of the tip element
40 is equal to about 5.0 mm.
[0064] The field of view 1510 is perpendicular to the optical axis
27 at a location within a volume of space that can be viewed by the
imager 1202 of the otoscope 1000. In accordance with the
orientation and shape of the opening 44b, the field of view 1510
has a circular shape (not shown from this perspective). The field
of view increases with increasing distance away from the opening
44b.
[0065] An object within the field of view 1510 is viewable by the
imager 1202 and is represented by a set of pixels within the imager
1202. The number of pixels representing an object within the field
of view is referred to as the resolution of the object within the
imager 1202. The resolution of an object within the field of view
1510 decreases as a function of the distance of the object from the
imager 1202.
[0066] The magnification of an object is a ratio of the size of an
image of the object, and the actual size of the object. Like the
resolution of an object, the magnification of an object within the
field of view 1510 decreases with increasing distance of the object
from the imager 1202.
[0067] A working distance 1530 is defined as a distance between a
location within the field of view 1510 and the distal most lens 96
of the otoscope 1000. The lens inset distance 1532, is defined as a
distance between the most distal end 44a of the tip element 40 and
the distal lens 96, and is equal to approximately 17.6 mm for this
embodiment. The tip offset distance 1534 is equal to a distance
between the most distal end 44a of the tip element 40 and a
particular object within the field of view 1510, such as the
tympanic membrane (not shown).
[0068] The optical characteristics of the otoscope 1000 enable
forming of light received through the distal opening 44a of the tip
element 40 without causing vignetting, which is the occlusion of
light from different areas of the field of view. As shown, rays of
light passing through the distal opening of the tip element 40 form
the distal entrance pupil 1420. The rays of light exiting the
distal entrance pupil 1420 expand towards the distal lens 96, but
the distal lens 96 is sufficiently wide and proximate to the distal
entrance pupil 1420 to intercept substantially all of the rays of
light exiting the distal entrance pupil 1420.
[0069] The field of view 1510 increases in size as a function of
the distance between an object within the field of view and the
otoscope 1000. In this embodiment, for example, at the opening 44b
of the distal end of the tip element 40, a location having a tip
offset distance equaling 0.0 mm and a working distance of 17.6 mm,
(pupil offset distance 14.54), the field of view 1510 has a
diameter of about 4.24 mm. The size of the field of view 1510
equals the size of the opening 44b.
[0070] At a tip offset distance equal to 9.4 mm and a working
distance of 27 mm, (pupil offset distance 23.94), the field of view
1510 has a diameter of about 7.0 mm. At a tip offset distance equal
to 20.4 mm and a working distance of 38 mm (pupil offset equal to
34.94 mm), the field of view 1510 has a diameter of about 9.85
mm.
[0071] FIG. 6A is a diagram illustrating the optical
characteristics of the human configuration of the otoscope 1000
with respect to a distance range of optimal focus. A distance range
of optimal focus is a range of distance from the otoscope 1000
within which the otoscope 1000 can provide optimal focus
adjustment.
[0072] By default, for the human configuration, the zoom
magnification feature of the imager 1202 is off. When the imager
zoom feature is off, the otoscope 1000 provides optimal focus for a
field of view located within a range of working distances between
22 mm and 38 mm, which are equal to tip offset distances of 4.6 mm
and 20.4 mm respectively. At optimal focus, the resolution is equal
to about 16 line pairs per millimeter. When the zoom magnification
mode of otoscope 1000 is on, the resolution is equal to about 28
line pairs per millimeter at optimal focus.
[0073] An object can be viewed with acceptable focus within a range
of working distances between 20 and 44 mm, which are equal to tip
offset distances of 2.6 mm and 26.4 mm respectively. At acceptable
focus, the resolution is equal to about 10 line pairs per
millimeter.
[0074] As a result, the nearest distance of an object from the
distal end of the tip 40 that can be viewed or imaged with the
optimal focus is 4.6 mm. The farthest distance of an object from
the distal end of the tip 40 that can be viewed or imaged with the
optimal focus is 20.4 mm. The above described optical
characteristics yield benefits when employed within a small and
confined body cavity, such as a human ear canal.
[0075] FIG. 6B is a diagram illustrating the optical
characteristics of the veterinary configuration of the otoscope
1000 with respect to a distance range of optimal focus. By default,
for the veterinary configuration, the zoom feature of the imager
1202 is on. In some veterinary embodiments, the zoom feature cannot
be turned off.
[0076] When the imager zoom feature is on, the otoscope 1000
provides optimal focus for a field of view located within a range
of working distances between 30 mm and 100 mm, equal to tip offset
distances of 12.4 mm and 82.4 mm respectively. The expanded
distance range of optimal focus accommodates much larger ear canals
possessed by some animals, such as dogs and cats for example.
[0077] As a result, the nearest distance of an object from the
distal end of the tip 40 that can be viewed or imaged with the
optimal focus is 12.4 mm. The farthest distance of an object from
the distal end of the tip 40 that can be viewed or imaged with the
optimal focus is 82.4 mm. These optical characteristics are useful
when employed within a small and confined cavity, such as a an ear
canal of a veterinary subject.
[0078] FIG. 7A is an illustration of a typical human ear canal 500.
As shown, the ear canal includes an opening 510 and a tympanic
membrane (ear drum) 530 located within it. A perspective of the
tympanic membrane (ear drum) 530 as seen from the opening 510 of
the ear canal 500, has a large profile, referred to herein as its
visible profile. The visible profile of the ear drum 530 shows
substantially one side of the ear drum, referred to as the visible
side of the ear drum. The visible side of the ear drum 530 is
somewhat circular in overall shape and has an average diameter
width of about 7 mm. Also, the visible side has a center point 532
along a surface that faces somewhat downward and away relative to
the opening of the ear canal, and is referred to as being
tilted.
[0079] A distance between the opening 510 of the ear canal and the
center point 532 of the visible profile of the tympanic membrane is
20 mm. Each cross-section of the ear canal 500, that faces and is
visible from the perspective of the opening 510, is also some what
circular. Because each cross-section of the ear canal it is not
exactly circular, each cross-section does not have a uniform
(constant) width (diameter) as a circular cross-section would have.
To address this circumstance, the width of each cross-section of
the ear canal will be defined as the distance from its upper most
surface to its lower most surface, which is discernable from the
perspective of this figure.
[0080] Accordingly, as illustrated, the width of the cross-section
of ear canal at its opening is approximately 8 mm. Moving from the
opening 510 towards the ear drum 530, the cross-section of the ear
canal narrows. At a location 512 of about 16 mm from the opening
510, the cross-section of the ear canal narrows to approximately 5
mm. Moving further towards the ear drum 530, the cross-section of
the ear canal widens to in excess of 5 mm at the ear drum 530.
[0081] Actual dimensions of each human ear canal vary across the
entire human population and a compilation of which forms a
statistical distribution. It is understood that the typical ear
canal 500 is located at or substantially proximate to the center,
also referred to as the mean or median, of the aforementioned
statistical distribution.
[0082] FIG. 7B illustrates a representative human 550 ear canal
that represents and approximates the typical human ear canal of
FIG. 5A. The representative ear canal 550 is a useful model that
illustrates the operation of the otoscope 1000 within an
environment that it is designed to work within.
[0083] The representative ear canal 550 has an upper surface that
is horizontal (level) and a lower surface is not parallel to its
upper surface and that rises gradually towards the ear drum 580,
and has a cross-section between its opening 560 and its ear drum
580 is circular in shape. The diameter width of the cross-section
of the representative ear canal 550 varies linearly between its
opening 560 and the ear drum 580. At a location of its opening 560,
the diameter of the representative ear canal 550, also referred to
as its width or diameter width, is equal to 8 mm. At a location 562
that is located 16 mm inside of the opening of the representative
ear canal 550, the diameter width of its cross-section is equal to
5 mm.
[0084] The diameter width of the cross-section of the
representative ear canal 550 varies and narrows linearly between
location 560 and location 562. The diameter width of the
cross-section of the representative ear canal 550 widens linearly
between location 562 and location 564 which is located at about the
center point 582 of the visible profile of the ear drum. The
location 564 is located 20 mm inside of the opening 560 of the
representative ear canal 550.
[0085] FIG. 8 illustrates placement of the tip element 40 within
the representative human ear canal 550. As shown, the tip element
40 is placed about midway into the ear canal 550. The distal end of
the tip element 40 is located 10 mm inside of the ear canal 550
from its opening 560.
[0086] At this location, the ear drum 580 is well within the
distance range of optimal focus provided by the otoscope 1000 in
its human configuration (See FIG. 6A). The range of optimal focus
starts a location 810 that is 4.4 mm from the distal opening 44b
(4.6 mm before the ear drum) and ends 20.4 mm from the distal
opening 44b, extending 812 well beyond the most distant portion of
the ear drum 580 and tissue surrounding the ear drum 580.
[0087] In this location, the field of view at the location of the
center point of the visible profile of the ear drum 580 has a
diameter of 7 mm, which is more that sufficient to encompass the
entire eardrum 580 within the formed still or live image. Using
focus position visual indicator 209, still or live image
information is obtained via the otoscope 1000 with optimal focus
and maximum visual acuity.
[0088] There may be circumstances where it is difficult to insert
the tip element 40 into the ear canal 550. For example, an ear
canal may be infected and/or be cluttered with cerumen (ear wax).
In these circumstances, the distance range of optimal focus
continues to enable image information to be formed with
optimal.
[0089] For example, if distal opening 44b of the tip element 40 can
only be inserted 5 mm into the ear canal 550, the ear drum 580 is
located 15 mm from the distal opening 44b and remains well within
the distance range of optimal focus. The field of view 1510 at this
location exceeds a diameter of 7 mm. Using focus position visual
indicator 209, still or live image information of the entire
eardrum 580 and its anatomical details (surrounding tissue) is
formed via the otoscope 1000 with optimal.
[0090] Even if the distal opening 44b of the tip element 40 cannot
be inserted into the ear canal 550 and is constrained to be located
at the opening 560 of the ear canal 550, the ear drum 580 within
the distance range of optimal focus. In this circumstance, the ear
drum is located 20 mm from the distal opening 44b while the range
of optimal focus extends to a distance of 20.4 mm from the distal
opening. Beyond 20.4 mm, the focus is near optimal and acceptable
within an additional 6 mm (See FIG. 6A).
[0091] Optionally, in this circumstance, the zoom magnification
mode can be set on. As a result, the ear drum and surrounding
tissue are entirely within the range of optimal focus (See FIG. 6B)
and the magnification is doubled to reveal finer detail to the
imager and the user.
[0092] FIG. 9 illustrates an image of a tympanic membrane formed
from the digital otoscope 1000 at or near optimal focus. As shown,
small details of the entire tympanic membrane including fine blood
vessels are visible from the otoscope 1000. These small details are
visible at a location in excess of 10 mm from the distal opening
44a of the tip element 40.
[0093] The following summarizes some of aspects of the invention.
In some embodiments, the invention provides for an otoscope
including an instrument head having a distal insertion portion for
insertion into an ear, the distal insertion portion having a distal
opening, an axisymmetric tip element releasably attached to the
distal insertion portion, the tip element having a distal opening;
and an optical system contained within the instrument head, the
optical system including a plurality of optical components and an
aperture stop about which the optical components are disposed, the
optical system forming an entrance pupil distal to the distal
opening of the distal insertion portion but proximal to the distal
opening of the attached tip element, the optical system further
including an image forming device that is configured to form image
information that represents a still or a live image of a target of
interest aligned along an optical axis with the distal opening, the
optical system being capable of capturing substantially the entire
tympanic membrane of a patient at one instant in time.
[0094] In some embodiments, the invention provides an otoscope
including an instrument head having a distal insertion portion for
insertion into an ear of a human or veterinary subject, the distal
insertion portion having a distal opening, an tip element
releasably attached to the distal insertion portion, the tip
element having a distal opening; and an optical system contained
within the instrument head, the optical system including a
plurality of optical components; and where the optical system
further includes a viewing component for viewing of an image of a
target of interest aligned along an optical axis disposed within
the distal opening, and the optical system being configured to
provide a field of having a diameter equaling at least 7 mm at a
distance of at least 15 mm from a distal opening of the attached
tip element; and the optical system being further configured to
simultaneously provide a distance range of optimal focus having a
range of at least 8 mm, the distance range of optimal focus
including a location at at a working distance equal to about 30
mm.
[0095] Optionally, the otoscope is configured so that the distal
opening of the attached tip element can be inserted into a
representative human ear to within at least 10 mm of a tympanic
membrane. Optionally, the optical system being further configured
to simultaneously provide a range of magnification of an object
within the field of view within a range of between about 0.4 and
about 0.6.
[0096] In some embodiments, the optical system includes an entrance
pupil having a diameter that is less than 5 mm and that is located
outside of the instrument head and within the attached tip element.
Optionally, the viewing component is an eyepiece including at least
one optical element. Optionally, the otoscope includes a focusing
mechanism that is user accessible and that moves a lens along the
optical axis. Optionally, the viewing component is an image forming
device that is configured to form image information and where the
device has a zoom magnification feature.
[0097] In some embodiments, the otoscope includes a focusing
mechanism that is user accessible and that moves the image forming
device along the optical axis. Optionally, the otoscope provides a
field of view equal to at least 7 mm at a working distance of less
than or equal to 35 mm.
[0098] In other embodiments, the otoscope includes a digital image
forming device having a zoom magnification feature, an instrument
head having a distal insertion portion for insertion into an ear of
a human or veterinary subject, the distal insertion portion having
a distal opening, an tip element having a distal opening; and an
optical system contained within the instrument head, the optical
system including a plurality of optical components; and where the
optical system having a tip element configured to penetrate at
least 5 mm into a representative ear canal and providing an
distance range of optimal focus having a length of at least 5
mm.
[0099] In other embodiments, the invention provides an otoscope
including an instrument head having a distal insertion portion for
insertion into an ear of a human or veterinary subject, the distal
insertion portion having a distal opening, a tip element having a
distal opening; and an optical system contained within the
instrument head, the optical system including a plurality of
optical components; and where the tip element configured to receive
penetrate a representative ear canal by at least 5 mm and receiving
a field of view having a diameter of at least 7 mm at a working
distance equal to less than or equal to 50 mm from the distal
opening.
[0100] Optionally, the field of view is received at a working
distance of less than or equal to 40 mm. Optionally, the field of
view is received at a working distance of less than or equal to 30
mm.
[0101] In some embodiments, a distance range of optimal focus has a
length of greater than or equal to 5 mm. Optionally, a distance
range of optimal focus has a length of greater than or equal to 10
mm and includes location at a working distance equal to 32 mm.
[0102] In some embodiments, the otoscope has a zoom feature.
Optionally, the zoom feature enables a distance range of optimal
focus having a length of at least 35 mm. Optionally, the distance
range of optimal focus includes a location of a working distance
equal to 65 mm.
[0103] In some embodiments, the otoscope is configurable where the
field of view is received at a working distance of less than or
equal to 60 mm.
[0104] While the present invention has been explained with
reference to the structure disclosed herein, it is not confined to
the details set forth and this invention is intended to cover any
modifications and changes as may come within the scope and spirit
of the following claims.
* * * * *